Field of the Invention
Apparatuses and methods consistent with the present disclosure relate to a display apparatus configuring a multi display system and a method for controlling the same, and more particularly, to a display apparatus configuring a multi display system through a transition minimized differential signaling (TMDS) channel and a method for controlling the same.
Description of the Related Art
In general, a display apparatus is a device displaying one or more images on one screen. However, the display apparatus may also perform a multi display function in which it is connected to a plurality of display apparatuses to display the image on a plurality of screens. A representative example of such a multi display system includes a video wall system.
A video wall means that the plurality of display apparatuses may operate as one display apparatus having a large screen by disposing the plurality of display apparatuses capable of outputting images in a plane shape to allow the plurality of display apparatuses to output a portion of one identical image transmitted from a source device. For example, the video wall is used to display an image in a form in which the respective display apparatuses configuring the video wall display the same image respectively, or display different images to be combined into one full image in an exposition, or the like. Such a video wall system is generally implemented in a loop out manner in which the connected display apparatus sequentially transmits the image to an adjacent display apparatus.
Meanwhile, when the image is transmitted by a transition minimized differential signaling (TMDS) manner, such a multi display system generally transmits the image through a high definition multimedia interface (HDMI) or a digital visual interface (DVI). In particular, HDMI, which transmits images and sound signals of a digital type using one cable, may easily transmit the images and sound signals using only a HDMI cable connecting between HDMI terminals. In recent, as a HDMI 2.0 standard supporting UHD images having resolution of 4K has emerged, the maximum bandwidth of data that may be transmitted through HDMI has been improved to 18 Gbps, and it is possible to transmit images that are smoothly driven at 60 Hz at resolution up to 4096×2160(2160p).
However, if the bandwidth used for image transmission exceeds the bandwidth supported by HDMI or DVI standards due to an installation environmental factor such as a source device, cable characteristics (defect of the cable, a support bandwidth of the cable), or the like, error occurs in the image to cause screen abnormal problems in that the screen does not appear or flickers. Since the image in which the error occurs is sequentially transmitted to the display apparatuses which are sequentially connected, screen abnormality occurs in all the display apparatuses receiving the corresponding image, starting from the display apparatus in which the error firstly occurs. As described above, in the conventional TMDS manner of the multi display system, since probability that the error occurs in the image is increased during the image transmission as the number of the connected display apparatuses is large, there is a limitation in the number of the display apparatuses capable of configuring the multi display system and it is difficult to transmit a high resolution image due to a problem of a bandwidth.
Accordingly, in a multi display system that transmits and receives the image in the TMDS manner particularly, it is required to search for a method for stably transmitting an ultra-high resolution image by implementing a loop out considering a state of the image signals.